Lee Valley Price for 48" Clamp 42.95.
That's quite a markup Robin.
Princess Auto claims they are the identical product, just a ton cheaper.
Is that true?

No, they're not the same product.

Lee Valley also has some inexpensive aluminum bar clamps (I saw them in a LV
store yesterday), that are price competitive with Princess. Starting price
is around $10 or so. And these look nicer than those at Princess Auto.

I think I have a pretty good idea of why people throw cans of food at you
and spray paint on your clothing. Probably more to do with your personality
than your actions.