I do love donating and helping in all that I can. Unfortunately, that's not always possible... I've had times go by when I've had to call out to others just to pay my rent and electricity (no lie, and not long ago)
The thing about donating that I love is that you can be sacrificial in some way. You may give $2 and it be a more heart felt gift than $100 from a large corporation etc.
Having a set, single price for software makes it more unattainable for poor people, and people who make much more are pretty much restricted to just the license price. If people gave in proportion to what they earned, it would be fair and right in the end IMHO.
This, of course, only applies to software that people actually use. If you do not use software, no point in making one give money to that unless they just want to.
At any rate, that's my 2 cents worth, take it or leave it.