I know we've heard this a thousand times, but it seems that there are still a TON of people that need to be reminded. DO NOT wear socks with sandals...Ever!
It amazes me the amount of women (and men) that will walk around town wearing a pair of socks with sandals. Apparently they either don't understand the concept of sandals (open, foot-exposing shoes), or they have lost every pair of sneakers that they own! Either way, this is an awful look and there is absolutely no excuse for looking that silly!
And wives (and husbands), don't let your spouse go out looking like this! I know it may seem like you're being mean by telling them that they look ridiculous, but it's better than the ENTIRE TOWN/People YOU Know, thinking that they look ridiculous, right?!
If that doesn't work and they continue to go with this look, get rid of the sandals! Throw them away, donate them to a thrift shop, whatever...just get them out of the house!