BA's Pricing

Now here's a funny thing, concerning the price quoted on the BA website for a first class return flight London/Beijing.

I was quoted a price of over £6500, were I to book a BA flight using the BA website.

However, the travel agency that I use quoted me a price of £4900 for the same flights. That is a saving of approximately 25%.

I wonder why there is such a discrepancy in quotes, given that the travel agency would still have to make a commission?

Needless to say, I made the reservation using the travel agency rather than the BA site.