Thirty-one arrests have been made across the Unite the Kingdom march and a pro-Palestinian protest.
The soldier, part of the Royal Horse Artillery, died at the scene after the fall on Friday evening.
Head of Meningitis Now wants to see a wider rollout after Oxfordshire sixth-form pupil's death.
Hundreds of people queue outside branches across the UK to get the £335 item.
Lloyd Jenkins and his parents pleaded guilty earlier this month to damaging a protected wildlife site.