What I've been doing with friends is telling them to go up to the departures level of T5, grab a seat and have a soft drink or water at the Goddess and the Grocer. Then when pick up time approaches is to walk outside to the end of T5 down towards TK (to the east) where it's not too busy.

Which LX are they arriving on? the LX2608 flight always seems to run earlier than the LX008.