Attitudes like this are what leads to systematic vendor lock-in and monopolies. If an open source system can't communicate with a proprietary system, the bug is one of these systems not following open standards.

I get your stance - but this is about a company trying to make money. If anything(such as avoiding vendor lock-in) gets in the way of you making money, then your venture is failing.

Card carrying FSF member here, but business is business.

I don't know, not for me. I still think it's possible to think of your business also as a political statement. Sure, you have to be prepared to 'pay' for your conviction, and possibly fail because of it. Which does not seem to make sense or be acceptable to a lot of folk. It is for me though.

Regardless of what you paid for a piece of software, if it is critical to your business operations you should be paying someone to maintain it for you.

If you were a small lawn mowing company and happened to receive a free mower for your operations, you wouldn't just run it into the ground without regularly paying someone to keep it in good repair (though this analogy does raise some interesting thoughts about companies in general and their maintenance policies).

In exactly the same way, you shouldn't be using software of any kind, paid or not, without having some plan for maintenance and repair.

If free software can cover the same business needs as paid software, there's no reason to not use it. But you absolutely cannot sacrifice maintenance just because you did or didn't pay money for the software itself.

If it's cheaper to buy a new mower every year and sell the used one compared with paying someone a salary to do maintenance then which would you choose?