Purchasing things online I sometimes use anonymized bitcoin, or prepaid credit cards purchased with cash. Most of the time I use bank cards like anyone else. Almost everything but appliances is shipped to a P.O. box.

IRL I only use cash which makes my movements around the real world mostly invisible digitally speaking. What I buy at the pharmacy etc is not tracked or sold to insurance companies, etc.

Never seen contactless payment be a hard requirement. Everyone takes cash eventually if there is a human to talk to, though I do sometimes end up using a frequently rotating prepaid credit card for things like parking.