Massachusetts has had one modern era wildly successful civilian high tech period, stretching from the minicomputer era to the early PC era (both Visicalc and Lotus 1-2-3 were done in the Boston area). But this part of its high tech scene died hard by 1990 (and I left the area, I was an eyewitness starting in 1979); non-competes were I believe part of the problem with Silicon Valley wildly out-competing the Boston area.
Since then I've heard things got better in the web era, but still nothing compared to the Bay Area.
If your product is superior in value, the salesman won't be able to move the customers away from your products.
Make better products.
Anyway, you'll attract better salesmen.
Additionally, these non-competes are often used in business where no meaningful additional data is shared, such as in the Dental field (e.g. they can't not share their clients with Dentists they hire, regardless of non-compete status). You may argue they would choose not to hire an associate in the first place, but then that leaves clients on the table for a new practice anyways. (empiric data would be a god-send)
Because you need to earn a living for one thing. And you won't keep your job for long as another reason (see strategic cases below because there are exceptions of course).
Anyway along those lines would you suggest that a salesman for jet engines for Boeing not take an order and simply tell the client that a Rolls Royce engine is a better fit for the application? (And yes I know that there are strategic cases where it can build loyalty by doing this and/or if the stakes aren't to large you can try to be helpful.).
So in other words the salesman's job is to, at the expense of the survival of his own company, to simply help the client (on his employer's dime) make the best decision and as a result he will still be able to earn a living because everything will just work out? And of course his competitors are doing the same thing, right?
Then make a better product, a more valuable product.
When an employer sends a salesman out to sell his product, he is sending him out on the company dime to wine and dine customers and get them to sign that contract for services rendered or product delivered. This costs the employer a great deal of money. The salesperson is worth nothing except for the relationships he can create between the employer and the client. These business relationships are created on behalf of the owner, not the salesperson.
So when a salesperson leaves a company and then decides to use the information he gathered during his tenure there to create new business elsewhere, he is essentially stealing what he was hired to create in the first place. I don't know of many companies that allow their employees to walk off with proprietary information, and information related to core business functions is certainly proprietary.
"Create a better product" doesn't fly. Anywhere. Not even in California. They simply call the list of customers a "trade secret" and sue your ass when you decide to start dialing them up at your fancy new employer.
Also, companies often like to hire experienced salesmen _because_ of their rolodex.
(Do they still use rolodexes?)
What happens when your previous employer fired you for using data you stole from a previous client?
Good luck taking years to build back your reputation.
I agree but I think there might be other legal (or see "know the customer yourself" below) ways to protect your clients.
So while you can't prevent someone from working for a competitor I believe there is a reasonable way to protect the customer list and/or specifically soliciting an existing customer. [1]
Nothing can prevent a client who knows the new business from approaching the salesman of course. But if the salesman is prevented from contacting them it is a bit of friction.
Separately, a way that you can protect against this is also to build some loyalty (as the business owner) with the client. Make contact yourself and let them know you value their business. Not fail safe but will definitely help. In other words multiple contacts, not just one contact.
[1] I've seen this even with hair salons for that matter. You will see ads which say "Joan is now at XYZ Salon" because Joan isn't allowed to go after her clients. But she can advertise that she has a new job. But not directly (by direct mail to a list of only her clients but she could spray direct mail though or advertise in the local paper because it's not targeted).
This would be really odd for salons. Most beauticians are contractors so technically they are her clients. She's paying the salon to rent their facilities. So salons get the best of both worlds. They skirt labor laws and tax laws.