my wife has been picked up a few times while shopping....even fucking or sucking them at the mall

Just be yourself and seem interested in striking up a conversation. Tell her you like to browse here at this store every week at this time. If you see her again you should be able to be more confident.
I've met a few younger lovers at the supermarket. They knew I shopped there every Saturday night at 10 PM. I'm in my late 40's and I am always flattered when I see them again the next week. I know they are interested and I am happy to see them. The key is to be discreet.

E,

Be yourself honey you have no idea we more mature ladies like it and appreciate it
Roxanna