Variety. If you pick up your comics weekly, you get a dose of many characters within the universe in one sitting instead of following endlessly down one narrow path of a single character's title.
Being up to date. By the time trades come out, the story feels old. You probably heard what happens already through reading the news. As true fans are appreciating what's currently going on in the universe, it's like talking about a boxing match way after it's over instead of watching it live with the world.
Appreciation of the art and story. A lot of times, when reading a trade, you go through a story arc non stop without breaks. All the cliffhangers turn into nothing. You don't get a chance to take a break and reminisce on that each of the issues and appreciate the small moments that made it great.
Consistency. With floppies, you get stories consistently whether it be monthly or twice-monthly so you are constantly in the zone. With trades, there's like 6-12 month gaps between volumes sometimes, and by then you're totally out of it. It's not like a new story arc is a total reboot or something, it really was just the next issue that was meant to come out a month later.
Fun. I like the individual covers and appreciating how individual issues had a guest artist or have something special happen such as a first appearance, a death, a revelation, etc. With trades, they jus mash all of it together. You could be flipping pages and then suddenly the artwork totally changes and you just gotta keep reading through.