If you want to know what is the price different for kinesiology tape,we must to know What are the main factors affecting the kinesiology tape price?
And the main components of the kinesiology tape?

Kinesiology tape in different parts.
main fabric,
spandex,
glue,
backing paper,
roller tube,
package
The kinesiology tape quality depend on main fabric and glue.
In the market the popular fabric in 3 styles:
Cotton
Rayon cotton
Nylon(Four way strech)

The fabrice GSM(gram per square meter) depend on the fabric quality.
In the market we can find more than 3 GSM.
150GSM,160GSM and 170GSM
The quality level 170GSM>160GSM>150GSM

There is different glue in the market too.
Germany Hankel glue ,Japanese Toyo Ink Glue,And Chinese hot met glue.
The quality level:Germany Hankel glue >Japanese Toyo Ink Glue>Chinese hot met glue
Also the glue's gsm can depend on the glue quality.
the popular 50gsm for kinsiology tape ,also we can find 40gsm in the market,