are HTIB speakers cheap quality then?
In general, yes. Some new comers think the receiver is the most critical part of their system. Wrong. Technology is to the point that most of the least expensive receivers can sound as good as most of the most expensive. Higher price gets you more power and more features.
One of the features higher price gets you is more amplified channels, like 7.1 or 9.1 instead of 5.1. The thing anamorphic96 is telling you is that when cost is a consideration, the extra channels for 7.1 are not worth it.
Most movies are mastered in 5.1.
In 5.1 systems, the side surrounds get mainly sound effect stuff, like doors opening, floors creaking, etc. By FAR, most of the sound still comes from your front Left/Center/Right.
In a 7.1 system, the rear surrounds get even less than the sides.
For a budget system, most people here will recommend:
get a basic 5.1 receiver, (no more than ~25% of your total budget)
get the best Front Left/Right you can afford
get the best Subwoofer you can afford
add a good Center when you can
add inexpensive L/R Surrounds when you can
HTIB packages will likely give you a better receiver than you need because it's easy to advertise features/specs of a receiver. They add inexpensive speakers, spending more on the surrounds than is necessary. They add an inexpensive sub that is easily bested in the marketplace. In other words, the priorities in a HTIB are not the same as the priorities agreed upon by most audiophiles.