I always use the internet as a starting point for negotiating....and it doesn't need to be a contentious or emotion based discussion.
I usually say "I'm willing to pay you more because I understand you have overhead and appreciate your convenience but I simply cannot justify paying 2 to 3 times more." (And yes I will say it just like that)
The worst thing that happens is I walk out with all the money I came in with.
Exactly this. I posted recently that I do the same with the manager of a 'local' B&M I go to. Just being open and honest, saying that you know how much the item usually retails for online, adding in that you expect to pay a little more to get it in your hand today and making an offer usually results in a win win situation. You get the item today, they make a few bucks that they probably wouldn't have made - everyone is happy.
Saying that, $150 for a TMAX is about $80-90 too much in my opinion. You can get them for around $40 online and I think I would have been a little disappointed - especially if I were a frequent customer.