Visited F-lounge at LHR T5 Friday afternoon. We noticed two persons grabbing a lot of beer and putting it in their bags. They had some round trips to the bar and even stopped to get more when leaving (all within 3-4 minutes) They noticed me filming, but looked like they couldn't care less. Guess they nicked 20+ cans and 5 bags of crisps.

See the video here

Showed the video to the lounge manager immediately, and he was speechless and he (and some more staff?) left the lounge to go looking for them. Don't know the result.

Based on the behaviour on these men, I guess it is not the first time. So look around. Managers office is by the entrance to the F-lounge. The staff at the front desk or in the cloakroom will probably be the best to notice and act fast.