I love five guys! Their standardized process avoids cross-contamination, just remind them to change the gloves. Had no problems with this location.
I have ordered from Five Guys four times from this store, and two times from their Marlton NJ store, specifically for their gluten-free option [no bun], and have not had a problem. My fiancee is very gluten-sensitive and can usually tell almost right away if she's consumed any gluten - even small amounts from cross contamination will set her reaction off - and she has never had a problem. The staff seems to understand gluten sensitivity issues. Having read other reviews that state cross contamination issues, I have to express some surprise. I've watched the burger creation process carefully, and at least in these two locations, the staff is very careful to avoid contamination. They also don't draw any extra attention to the gluten issue or disrespect it in any way, unlike a surprisingly large number of chain eateries, which seem to feel that gluten sensitivity is a topic to joke about or patronize. I highly recommend Five Guys Deptford [and Marlton] for gluten-free options.
My daughter has celiac. She ordered the lettuce wrapped burger and fries. I told them allergy, and asked they be bagged separate. The line was mostly ok with some minor issues but they did change gloves. The problem is the lady doing the fries kept going and touching and sweeping the counter with her hands, moving the sandwich wrappers along the line, and going back to the fries. She did change gloves once but not before potentially contaminating the fryer/fries. I would not bring my celiac kiddo here again.