Many prefer a USPS money order , but I will no longer accept one.
Although the gun Community does not do counterfeits there is that concern outside of the gun community.
My primary reason for not accepting them is because most of the post offices in my community are unable to cash them over $75. They cannot be deposited on your smartphone to your bank and if you do not have a bank local to you (my current predicament) they cannot be cashed at all.
People can have their Bank send a check directly to me for no charge in most cases or they can write a personal check out of an old fashioned checkbook.
Others May disagree, but I've never had a problem with a check from a 24-hour campfire member.
