Bcoz spiritual channels get good revenue thru kathas / pravachans which r aired on them. Time slots r booked by respective katha vaachaks / spiritual organizations and channel gets payment for same. So basically these channels have a good viewership which is translated into revenue thru content aired on it
Other channels do not have that convenience and have a ratings/subscription/ad revenue driven business model
Also this is just HD feed on YouTube, Sanskar channel had plans to launch HD Channel on satellite platform too but i guess that plan was shelved bcoz of financial viability reasons