1 Mayo on fries?  Ugh.
If you put bacon on that, and used a Mexican three- or four-cheese blend, you'd have something close to Outback Steakhouse's (or many other places') cheese fries.

2

In the Netherlands, if you order french fries they come with mayonnaise. But this goes back even further.

When I was a young coot (high school) there was a hamburger chain in these parts called "Arctic Circle" which had a special dipping sauce for their fries instead of ketchup. Took me a long time to figure out that it was a mixture of ketchup and mayonnaise. I always really liked it.

Apparently the chain still exists, but the local restaurant closed during the period when I lived elsewhere, and now there's a Mexican fast-food restaurant there.

3 Mayo on fries is heretical! And like many other heretical things, not half bad really.

I have a cousin-in-law who's from the Netherlands and once described a french fry vendor who had over fifty kinds of flavored mayo for dipping...

4 Looks tasty. Add a little bacon as already suggested, and maybe some ranch dressing, even more tasty.

I've never cared for mayo on fries, but I don't really like mayo on anything. I usually put BBQ sauce on fries.