Whatever anyone thought of the wedding, Edward was determined to give the couple a wedding to remember. Jewels were presented to the couple, Margaret received a palfrey worth £20, and pennies to the value £7 10s 6d were thrown over the couples heads at the church door. The ladies-in-waiting received cloth of gold and pearls as presents. The king himself attended, as did the Earl of Pembroke. Edward was in a generous mood - he made a payment to Richard le Kroc of Berkhamstead of 5s for damages caused to the property during the celebrations.
The historian Seymour Phillips makes the point that Gilbert de Clare would never have agreed to marrying his sister to Piers if Edward and Piers had been lovers. Likewise, he says Phillip 4th would never have allowed his daughter Isabella to marry Edward if he knew of the relationship. I think this is a very naive point of view. Marriage contracts were usually arranged and signed without due regard to the bride's feelings. Gilbert de Clare was close in age to both Piers and Edward, and would have known what the relationship between the pair was. He would also have known both Edward and Piers would have wanted marriages - it was their duty to marry and hopefully provide heirs. His sister was strengthening family ties by marrying the King's favourite. The fact Piers was Earl of Cornwall, and his sister would now be a Countess, added to the honour and prestige of the family. We don't know what Margaret's views were, though she if often portrayed in historical fiction as a naive, unwilling girl - but she was only 14, knew her duty to her family and her king, and who knows, she may have just found the charismatic, handsome and impeccably mannered Piers to her liking.
This is an aerial view of Berkhamstead Castle - all that remains of it.
Source: Hamilton's 'Piers Gaveston, Earl of Cornwall'.
Seymour Phillips 'Edward II'