Probably a combination of “it’s really important to this person” and “love”. Switching to what your loved one supports happens with all faiths, and occasionally, even football teams.

I have no problem with that.

I do, however, have a problem with that actually meaning “they have to support Israel’s genocide” or “they have to arrest anyone who says mean things about Israel”.

I suspect you could burn a Union Jack in the middle of your City Centre and there’d be no legal response to it (assuming you had an adequate fire risk assessment).

I also suspect if you burnt an Israeli flag in the middle of your City Centre that you’d be quickly arrested for “terrorism”.