"A strange custom, since they don't care one way or the other."

Presenting your house to the public is a strange custom.

How did people come to drift into such a strange custom?

"Because you apparently have not heard of strange customs that exist there."

I am no Reader, nor bound by your strange customs.

It must be some strange custom from across the Great Water, he decided.

It's a strange custom when you think about it.

He was aware that strange customs were still practiced among the country folk.

It helped me cope with the strange customs of the Americans.

Also they had several strange customs of which they did not know the origin.