They can help people put up to 65535 services on a single IP address rather than taking up a /16 of routable space through port numbers alone. Double that if you add UDP, and triple that if you can find that many services that can use SCTP.
You still need at least one IP address, but for services using hundreds of individual hosts the cost shouldn't rise too much this way.
What common applications commonly support SRV? I can't load a HTTPS in a modern web browser on a non-443 port without explicitly specifying it for example.
You still need at least one IP address, but for services using hundreds of individual hosts the cost shouldn't rise too much this way.