No reason the company cant do that, usually, but it's not advantageous for (most) employees. RSU comp is taxable on vest, but if the stock is not liquid the employee must pay out of pocket at each vesting event to cover the taxes.
Disclaimer: this is not financial advice.
I'm not sure if this approach would make sense after any sort of traction/fundraising.
I’m in the job interview process right now
Looking at a pre-IPO company with RSUs
Does this mean that I pay taxes on those RSUs when I get them, _even_ if I don’t sell them?
Since your company is pre IPO, they may have a dual trigger vesting schedule, where shares vest over time but require an actual liquidity event for you to actually receive the shares, giving you no tax liability while the company isn't public. However, this means that once the company goes public, you'll have to pay all of that liability at once, at ordinary income tax rates.
Disclaimer: not an accountant, much less your accountant, this is not financial advice, seek proper advice from a qualified professional.
If you're getting N years of windfall-level income in one year, some of the income is likely to be in that top bracket. This means that all sorts of tax stragegies you probably are not familiar with will kick in.
For instance, it might make sense to move charitable contributions into that year, since the IRS will effectively be matching them.
Also, AMT will probably kick in, so consider hiring an accountant.
What this does mean, though, is that until the second trigger is hit you haven't technically vested the RSUs. So you get around the taxation but there may be additional conditions on your equity.
Basically - make sure you read the stock plan
And pay a lot more tax in the process, than if you were able to exercise early. IRS always has to have its cake and eat it.