Specialty pliers are designed for specific jobs, making those jobs much faster and easier. They can pay for themselves in one job for techs working flat rate, but DIY repairs may end up costing a lot more if the tool is only going to be used for that job, so it is a trade-off to consider.
Relay pliers are shaped specifically for grabbing automotive relays and pulling them out. They can also be used to pull out some types of fuses.
Lisle 46950 Relay Pulling Pliers
Oil Filter Pliers
Oil filter pliers have a large round opening to grab on to the case of an oil filter.