It would be fascinating to see the word "lifestyle", as applied by this particular employer, thrashed out at a tribunal.
Theft suspected but, as yet, unproven? We're all at risk of sacking if excuses that flimsy can stand up in dismissal cases.
Poor timekeeping is trivially easy to document and use to fire someone. As are the results of random drugs testing, which is the only thing I can think of which fits the word. If they're falling out of a nightclub at 3am, they're hardly going to be effective in the workplace by morning.