It's useful because, with an abundance of plated-through holes, it's easy to securely mount through-hole parts, such as leaded resistors, capacitors, LEDs, etc, and DIP ICs. Once the parts are mounted, it's straightforward (if tedious) to run wires to make connections as needed, and the pads make soldering the wires that much easier.
There is a tradeoff here. With no strip connections in place, you can't just plug things in. What you get it return is the ability to make compact layouts with low interconnect resistance, since you don't need to deal with the predetermined strips. For any degree of high speed, you'll get better performance with what you've got than a stripboard would give. It's not as good as a multilayer PCB, particularly one with a ground plane, but with care it can come very close.
Likewise, if you're doing anything that requires higher currents, more than, say, 100 to 500 mA, with perfboard it is straightforward (and again, tedious) to use larger gauge wire as necessary.
If you do much perfboard work to prototype circuits, you'll be much better prepared to consider layout concerns if you ever graduate to making PCBs.
Although it is, to be honest, a pain in the butt to have to solder/desolder mistaken connections, rather than just pull the wire out and plug it in elsewhere. And you can't reuse perfboard nearly as easily as you can stripboard.