Yeah, that would be the logical response, but hard to accept sometimes...there are so few vendors, and even with the "difficult" ones (save K&S, I rejoined the hobby too late to order from them), my experiences have been mixed. Some people got shafted by RW, for example, but my orders (3 or 4) had all been very smooth. Same for Red Arrow- have had a little heartburn, but was never left incomplete. If I received (or heard about) consistently poor service, then yes, I advocate for a boycott, but crap happens, and as we all know, these are not millionaires sitting poolside enjoying cocktails and burning $20s to light their cohibas...these are regular Joes trying to support their and our addic...er, hobby.
I also tend to be cheap, though, so I go for the lowest price to stretch my limited hobby budget. If it's a mission-critical part, or if I'm attempting a cert and have a window, I do tend to err on the side of safety, and order from the folks that consistently over-deliver (Apogee, Mad Cow, among others), which commands a higher price.