In adobe export pdf>marks and bleed>bleed: set inside bleed to zero (0).
That's what you should be expecting to see when you have an inside bleed allowance set. The inside bleed area is the edge of the opposite page. In your image you haven't bled anything on the spine, so you don't need the inside bleed, but if you have a crossover this is exactly what you want. If you have objects, like you color bars, that run to the spine and actually need to bleed without appearing on the opposite page, see InDesignSecrets » Blog Archive » Breaking Pages Apart to Bleed Off a Spine