He's probably just curious, too. My kitten is intrigued by the plants
being watered. When I pour water into her dish, she watches and seems to
think I've turned it off (she loves the bathroom sink and running water
- I sometimes think that's the only water she's drinking. She laps up
the tap water as its warming up for me to wash up in the morning and
leaves when it gets too warm for her.). BTW, I groom her a lot, so
there's never any cat hair on the sink. She sheds less than my daughter
and husband.
Kathy P.
NJ

Presumably, these bag handles have been carried by yourself and will have
your scent on them.  Perhaps your cat is chewing these to 'taste' you, in
just the same way a cat licks itself after you've stroked it, to taste your
scent and to reaffirm his bond with you.  The fact that you've been away
from him whilst shopping would seem to confirm this.  Just an idea ..

Cats famously prefer to drink almost any water except that which you've put
down for them.  I don't allow my cats near any surface or facility which is
required to be hygienic so I don't see them drinking at domestic taps, but I
do observe them drinking from puddles, from our pond, and (as with your cat)
from drainage saucers under plants.  My only concern is that they might
drink from a saucer with a high potash feed added (or indeed any chemical),
so I feed my pots with care while the cats are sleeping.

Glad to hear your puss is well.

Spider