In any case, Glyndebourne is different, it's a whole experience: its setting in the South Downs, its history (established by the Christie family in 1934 - same year as the British Council), its context adjacent to the beautiful 16thC Christie house, its incredibly loyal fan base (all performances sell out; you have to kill for tickets), the black tie dress code, the picnics on the lawns and the intimate atmosphere of the theatre itself. It started out as amateur dramatics but quickly became professional, outgrowing its piecemeal-developed theatre until a completely new one was built in 1994. What's particularly interesting is that it was paid for largely (90%) by its fan base, and the whole caboodle still operates without Arts Council funding (as opposed to the Royal Opera House, for example, which receives £26m p.a.).
Anyway, it was all most enjoyable. We brought a picnic, but because of the inevitable rain, set it up in the semi-covered perimeters of the theatre which seemed to be designed for it. In fact, it was so full of little tables, each with neat table-cloths, champers in ice-buckets, even vases with flowers, that it took a while finding a spot.
Interestingly, I just read the audience comments on the Glyndebourne blogsite and found the following: "We live in China for much of the year but look forward immensely to Glyndebourne on our annual summer visit... We would not have missed this production for anything. It was terrific." It wasn't us, but I would echo it. Thank you Renzo & Annette!