How to use vanilla beans?
Vanilla extract is essentially vanilla infused into alcohol. If you don't have any problem with storebought vanilla extract, I doubt you'd have much problem with homemade vanilla infused into alcohol (i.e. homemade vanilla extract) either. While people do sometimes describe real vanilla extract as "boozy", it's not so much about the alcohol as the vanilla flavor. Some do still like it a bit less, though.

Infusing into oil will certainly work, but it does introduce botulisum concerns if you want to store it for very long. So you're much more likely to see it infused directly into a high fat food like ice cream.

For ice cream, you scrape the contents of the bean into the warm custard mixture (milk/cream/egg), and let it steep for 20-30 minutes. (You can also put the whole bean in and fish it out later.) The heat and the fat content both help extract the flavor.