Whenever someone says they "have" to use proprietary software I am immediately suspect.
This is a good read, I think: http://www.ebb.org/bkuhn/blog/2010/08/09/have-to-use.html TL;DR version: What they really mean is that they "want" to use proprietary software, not that they "have" to. Helpful for re-framing the issue, I think.
