True enough, but I'm not willing to go toe-to-toe with them unless I have a list direct from the IRS that contradicts them. I can't find such a list. You wouldn't by any chance know where I could find it, would you?
UPDATE: OK, I did some looking around, and according to the IRS, sunscreen is classed as a "dual-purpose" item. Things on the dual-purpose list are essentially iffy, and the IRS allows plan managers to require a prescription for reimbursement for those if they want to do so. Mine wants to do so.
I looked at every bit of plan documentation I could find online, from all kinds of providers. It turns out that they are all over the place on sunscreen. There are several plans, like United, that require a scrip before they will reimburse. Others set an SPF rating limit: some use 15, some 30, others 45. Several say that they SPF rating must be noted on the receipt or they won't reimburse.
Bottom line seems to be that sunscreen is an item that the plans get some leeway to decide on, and some plans may be more strict than others.