Well this is really a tricky question. Have I done this, Yes. Will i buy from that shop if they are within 10-15%, Yes. Will i pay $1000 for a $400 Semi-Dry suit, Hell no....but i will find one to try on to make sure it fits!
These shops get bent because people are buying online, but they wont make themselves more competitive by making a 30% profit instead of a 120% profit. They are taking themselves out of the competition and blaming it on the guys that give customers a fair shake.
I can't speak for all dive shops, but the overhead for brick-and-mortar stores is generally much higher per item and the volume much lower than on-line shops. I think one has to understand this and not get outraged when prices at the LDS are higher. Of course this excludes pricing that truly represents gouging of new divers, but I have no problem with the LDS charging a price that gives them a reasonable profit. After all, I want them to stay in business so I have somewhere to go!
Of course I generally wear my wetsuits until they fall apart (current 3/2mm Tilos is 9 years old) although my Henderson Neosport is a youthful 2 years.