That is a GREAT attitude, Gene!  Insistent, unsolicited assistance really hacks me off too, as in most cases, especially when getting my chair into our vehicles, the "help" is cumbersome, time-consuming, and typically winds up making the experience more difficult than it needs to be.  But making somebody feel good about themselves is one of the best gifts one human being can give to another -- giving by graciously receiving, I call it.  One upside to this sitting life is that we, as PWDs, get to see a side of humanity that most ABs don't.  So, when I get that simple offer of assistance that I may not need, I always respond with something like, "I'm in pretty good shape, but thanks so much for asking!" so as not to discourage them from asking the next person they see in what they perceive as difficulty.