One of my former coworkers helped build a ridiculous iPhone ringtone app a few years ago that STILL generates positive cashflow, and profited several 100k. This was done strictly through marketing. There are plenty of ways to grow a product, but these guys didn't have the know-how or wherewithal to do it for an already profitable product.
A real business person would have taken that $75k/yr and figured out a way to grow it, through marketing, by pounding the pavement, etc. Most startups are cash flow negative, and will die in a year and yet this company generating profits and weren't able to make it grow? They gave up way too easily, and like people said, it's because they got bored of it. That reeks of arrogance, sorry to say, being bored of $75k/yr.
Hopefully your current products are profitable, so that this isn't a lesson that comes back to haunt you later on. But as other people said, I also hope this doesn't mean that your current customers have to look forward to their product being closed down prematurely because your company got bored of it as well.