How can I make it clear from my invitations that while I love kids, I don't love them at my wedding? I want to have no kids at my wedding, but I don't want my guests to be mad at me. Is it even possible?
As usual, my recommendation comes down to being proactive instead of reactive. Instead of making it negative (“How can I say ‘NO CHILDREN ALLOWED'?”), simply pick a venue and time that support adult-only activities. In other words, have a night wedding at a 21+ venue like a bar or lounge. There's nothing like an 9pm ceremony and a dude checking IDs at the door to keep the kiddlets away.
It might sound like I'm joking, but I'm totally serious. It's pretty much impossible to have a child-free afternoon wedding without hurting someone's feelings, because it's clear that you're the one making and enforcing the NO KIDS ALLOWED rule. Then people get frustrated with you. As a guest, most don't want to hear about what they can't do at your wedding, who they can't bring, or what they can't experience.
Weddings in family-friendly locations like parks and gardens and restaurants and churches are usually family affairs, and you're fighting a challenging, uphill battle trying to turn these family venues into something they're typically not. When you try to say “no kids” at a venue where kids are usually allowed, it makes you the meanie bouncer who's in charge of telling your guests what they can't do. (“Yes, I know it's a lovely garden with a big lawn to play on, but please understand NO KIDS ALLOWED.”)
But a bar? It's obviously an adult-only venue, and bar weddings and bar receptions are awesome. When you have your wedding at a swanky lounge or reserve a rooftop hotel bar for your reception, it's not your responsibility to enforce the rules or figure out how to word the invitation. You can outsource your bouncer duties to the guy at the door checking IDs and the liquor control board.
On your invitations, just note (Venue is 21+) on your invitations. Here's an example of a lovely design that we hacked example text into:
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