Vintage Cars: Oil filter gaskets and spin type can filters, ring gasket, rubber gasket

Question
When changing the spin-type can oil filter on US cars since the 1960s, I was trained to ALWAYS apply a fingertip swipe of fresh oil around the rubber ring gasket before installing it. Supposedly, this helps to make a good seal and prevent leaks.

But after years of doing this out of habit, it occurs to me that petroleum rots rubber... (and that's the reason why oil-based lubes are NEVER used with laytex condoms, and other rubber products).

So, what's the real story here? Why is a rubber gasket ring used when exposed to high heat, pressure and oil circulation? Or am I missing something obvious here?

Any  comment? Thanks.

Answer
The seal is made of a type of rubber that is impermeable to oil and petrol.
Less so for petrol since cars with fuel contaminated oil do tend to leak from gaskets and seals after a while.

Personally I coat the ring in oil on both sides, it helps it to sit properly - if you put it on without lubrication and the rubber grips while tightening it can bunch up, kink and leak.

The rubber can withstand 240 degrees Celsius or so.