Instead of taking the Banff Gondola to the top of Sulphur Mountain, consider hiking to the summit instead. Enjoy the same amazing views of Banff and surrounding mountains from the top, all without the full gondola fee.
The 11km return trip includes 665m of elevation gain. Needless to say, prepare for the journey to be uphill all the way. It's a solid moderate hike in summer and becomes more difficult in the cooler months (microspikes required).
My friend Leigh (HikeBikeTravel) has written a comprehensive guide about the hike. It is possible to take the gondola down instead of hiking, but there is a fee.
A Parks Canada parks pass is required to explore Banff National Park ($22/day for a vehicle of up to 7 people).