Why is This a Thing?

My reaction is much the same as yours, Pappy. It desecrates both flags and puts ours lower than theirs. Of course, we're on the hoist end, which I think may be more prestigious. However, I think two flags on separate poles are the appropriate way to do this.

on the border ?

At least a six hour drive north of the 49th parallel (US border).

This really is a strange mésalliance;-) In my backpacking days Canadians nearly always had the maple leaf on their backpacks for fear of being mistaken for US Americans...

????

Well, that's a first for me.... I've never seen a mash-up of two flags like this -- and I'd seen millions of flags in my lifetime. I dunno that I'd call it offensive -- no more so than making a beach towel out of a nation's flag --- but I would call it strange. More garden deco. than flag(s) really.... Anyway, nicely captured!