We were lucky to have done a lot of traveling before children. A typical vacation pre-kids involved Gortex boots, cold weather gear, car hire, multiple flights, street clothes for hard to book restaurants, shows, museums and walking tours. Great memories.
The thought of such a vacation with 4 children? I'm exhausted and I haven't even finished packing yet. Not to mention the kids would grow out of their Gortex boots before the plane even lands, airlines lose my prams and car seats, Hertz fails to reserve the van I booked months prior, and countries that do not mandate disable access in public premises just can't be done with prams. We did manage Whistler when we only had two kids. But I needed a vacation after that trip!