Mr. Bingley was no Mr. Collins. I think almost any woman whose heart was not already engaged elsewhere would have grown to love Bingley and respected him. He was sensible, friendly, well-mannered, lively, and liked by all, besides being handsome. So I don't think a woman who married him without being in love could truthfully be called mercenary. His eligibility did not just depend on his L5000. Charlotte said something else in that conversation with Lizzy that may here be proved true (thanks for bringing this up, so that I could notice this!):

There is so much of gratitude or vanity in almost every attachment, that it is not safe to leave any to itself. We can all begin freely -- a slight preference is natural enough; but there are very few of us who have heart enough to be really in love without encouragement.

If Bingley had been helped on through either gratitude or vanity, he may have been persuaded to drop his suit when he thought he had no cause for either. Certainly, his pride (the kind in good regulation, I think) would have been hurt. I am not sure what his thoughts about Jane were now beyond this.