I had just this issue about a month ago - leaving for a two week trip with umpteen meetings, forgot to pack the ties.
I had a mild heart attack at the prices of ties, and the hideousness of some of them, in T5, ended up getting the hotel concierge to sort some out for me when I landed. Worked out a lot cheaper, even after tipping the guy for bringing a selection to choose from and taking the rejects back to the shop!