Bargaining power of suppliers

Does the answer to bargaining power of supplies should always be either high or low?

I mean, what if company has suppliers for different types of materials? In that situation, the bargaining power would depend on which material you have a supplier of right?
For example, suppliers like Boeing and Airbus have high bargaining power against an airline company in terms of supply of aircrafts.

However, the airline company can have a high bargaining power against suppliers of maybe food items or flight crew staff?