Platforms like Expedia negotiate group rates with hotels and resell them cheaper than the direct site, so you're right to find that weird but it's totally normal. The hotel often displays higher prices directly because it accepts those conditions for the visibility Expedia brings. If you really want to negotiate, call the hotel directly before booking and explain that you found something cheaper elsewhere - some will agree to match it or lower the price a bit to keep the commission they'd make with Expedia, but honestly it's not guaranteed. Otherwise the best thing is just to compare three or four different sites and go with the lowest offer.