You can train your scalp to be less oily. A lot of the time your hair is oily because of too much washing with harsh shampoo. My DH used to wash everyday and is oily by evening. He started switching to gentler shampoos. Then he started skipping a day. It took a while but I think his scalp has adjusted. Now he's mostly doing conditioner-only wash, every couple days. He only uses shampoo once every week or two. His hair doesn't look oily at all.
I stretched my washing schedule to every 3 days and I'm happy about it. I use shampoo bars and they're quite gentle.
Mom to 2 beautiful autistic boys (13 & 12)